What is the best way to conditionally apply a class?

Question

Lets say you have an array that is rendered in a ul with an li for each element and a property on the controller called selectedIndex.

Answer 1

Here is another option that works well when ng-class can't be used (for example when styling SVG):

ng-attr-class="{{someBoolean && 'class-when-true' || 'class-when-false' }}"

(I think you need to be on latest unstable Angular to use ng-attr-, I'm currently on 1.1.4)